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941.
942.
铝电解电容器用国产电极箔发展概况 总被引:2,自引:0,他引:2
论述铝电解电容器用国产电极箔的现状和发展趋势。分析我国电极箔生产厂家在生产规模、工艺技术和产品质量等方面同国外同行间的差距。探讨国产电极箔的发展前景。 相似文献
943.
944.
分布式多媒体同步中表现质量的参数计算 总被引:11,自引:0,他引:11
分析并量化描述了分布式多媒体通信同步及连续表现问题。提出了源和目标结点间因网络传输延迟不确定性而导致的多媒体数据流传输与回放速度不匹配的3 条解决措施:①源和目标结点在发送和接收多媒体对象时遵守时序制约关系;②在缓冲区中预置若干多媒体对象;③采用有界缓冲区。本文定量计算与证明了源结点的最迟发送时间以及目标结点预取的最大与最小多媒体对象数,并在实际应用中得到了验证 相似文献
945.
图象质量的主观评价按评价方法的单项要素有;色纯,会聚,高度和色度分量间的重合,灰度绝调,几何失真和图象重显度,灰度重现,彩色满意度,图象干扰等,此外还有“清晰度”和总的图象质量”,在其它要素较好的情况下,这两个要素决定了彩电的技术水平,为提高图象质量采用了各种动态调整技术。 相似文献
946.
M. Plebani 《Accreditation and quality assurance》1999,4(3):84-86
The transition from quality assurance of the analytical phase to the quality management of total testing in clinical laboratories
is still at an early stage. But it has begun. Accreditation through voluntary, educational and professional schemes, like
the Clinical Pathology Accreditation scheme, is a useful tool for following defined standards of practice and having these
independently confirmed on the basis of a peer review. Approved clinical laboratories can obtain a hallmark of performance
and offer reassurance to users of their services. However, accreditation does not guarantee an error-free service; it is not
the final step, but an important stage in the improvement process. Quality is a journey and continuous quality improvement
is the paradigm for better addressing our efforts to satisfy customers' expectations for the desired health outcomes related
to a high-quality laboratory service. 相似文献
947.
V. Dvorkin 《Accreditation and quality assurance》1999,4(5):207-211
The history and the present condition of external quality assessment (EQA) schemes for clinical laboratories in Russia are
described briefly. The creation of EQA programmes started in Russia in the 1980s. Now almost 20 years later these schemes
have been transformed. The National External Quality Assessment Scheme ensures quality control in the clinical chemistry sector
(more than 2000 laboratories) and is the most powerful scheme in Russia. The (Sistema Vneshnego Kontrola Katchestva, *) (BKK)
system, covering about 120 Russian laboratories, and a lot of local regional programmes (mainly in Siberia), is also very
active. The purposes and design of the operating programs, reference materials used, algorithms of estimation, modes of result
representation and development prospects are considered. The basic obstacle to the development of EQA schemes in Russia is
financial restriction. 相似文献
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Modern thermal analysis, microcalorimetry and new emerging combined techniques which deliver calorimetric, microscopic and
spectroscopic data offer a powerful analytical battery for the study of pharmaceuticals. These techniques are very useful
in all steps of development of new drug products as well as methods for quality control in production. The characterization
of raw materials enables to understand the relationships between polymorphs, solvates and hydrates and to choose the proper
development of new drug products with very small amount of material in a very short time. Information on stability, purity
is valuable for new entities as well as for marketed drug substances from different suppliers. Excipients which vary from
single organic or inorganic entity to complexes matrixes or polymers need to be characterized and properly controlled. The
thermodynamic phase-diagrams are the basis of the studies of drug-excipients interactions. They are very useful for the development
of new delivery systems. A great number of new formulations need proper knowledge of the behaviour of the glass transition
temperature of the components. Semi-liquid systems, interactions in aqueous media are also successfully studied by these techniques.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献